The inventors of the present disclosure have sampled the water samples of An-tong hot spring in Hualien County, Taiwan. Then, a novel bacterium of Tepidimonas named Tepidimonas fonticaldi sp. nov. in the water samples was isolated and purified. Extracellular proteins secreted by Tepidimonas fonticaldi sp. nov. have excellent effects for binding metal ions, and are not influenced by environmental conditions, such as high temperature, high pressure, or pH value. Therefore, the extracellular proteins secreted by Tepidimonas fonticaldi sp. nov. can prevent metal salt scaling, especially calcium carbonate, from being formed in boiler equipment, underground pipelines, geothermal wells, industrial wastewater or hard water, to maintain the proper functioning of the machines and reduce operating time and costs.
Bacteria of genus Tepidimonas are bacteria which are gram-negative, strictly aerobic, oxidase- and catalase-positive, rod-shaped and slightly thermophilic bacteria.
However, the growth and self-protein metabolizing rate of bacteria of genus Tepidimonas are slow, and this makes it hard to obtain the protein. Therefore, a novel method of producing extracellular proteins from genus Tepidimonas is needed.